如何告诉HtmlUnit的WebClient下载图像和CSS？

如何告诉HtmlUnit的WebClient下载图像和CSS？

我现在正在做的是：

public static final HashMap<String, String> acceptTypes = new HashMap<String, String>(){{        put("html", "text/html,application/xhtml+xml,application/xml;q=0.9,**;q=0.5");        put("script", "**;q=0.1");    }};protected void downloadCssAndImages(HtmlPage page) {        String xPathexpression = "//*[name() = 'img' or name() = 'link' and @type = 'text/css']";        List<?> resultList = page.getByXPath(xPathexpression);        Iterator<?> i = resultList.iterator();        while (i.hasNext()) { try {     HtmlElement el = (HtmlElement) i.next();     String path = el.getAttribute("src").equals("")?el.getAttribute("href"):el.getAttribute("src");     if (path == null || path.equals("")) continue;     URL url = page.getFullyQualifiedUrl(path);     WebRequestSettings wrs = new WebRequestSettings(url);     wrs.setAdditionalHeader("Referer", page.getWebResponse().getRequestSettings().getUrl().toString());     client.addRequestHeader("Accept", acceptTypes.get(el.getTagName().toLowerCase()));     client.getPage(wrs); } catch (Exception e) {}        }client.removeRequestHeader("Accept");}